Possible candidates for supplying this water are comets. Because of their large ice content, comets from the outer solar system were leading candidates for many years, but then analysis threw doubt on the idea. The water in these comets was shown to differ chemically from ocean water; it has a higher incidence of deuterium--water with an extra hydrogen atom.

But then, recently, a closer band of comets has been discovered which have the "right stuff." In 1999 a member of this band shattered upon its approach to the Sun allowing astronomers to analyze its composition. Unlike its brethren which circle much farther out in the solar system, this closer family of comets has the same kind of water that makes up the oceans, breathing new life into the idea that the comets provided much of the water on earth.

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Foolishness! Your DNA would actually stretch to the sun and back about 4 times!

DNA is a fine, spirally coiled thread in the nucleus of every living cell that serves as a guidebook so the cells "know" what they're supposed to do. The strands are so fine you need a high power electron microscopes to see them.

The human genome, the genetic code in each human cell, contains 23 DNA molecules each containing from 500 thousand to 2.5 million nucleotide pairs. DNA molecules of this size are 1.7 to 8.5 cm long when uncoiled, or about 5 cm on average.

You have about 10 trillion cells in your body, so if you stretched the DNA in all the cells out, end to end, they'd stretch over 744 million miles. The moon is only about 250,000 miles away, so all your DNA would stretch to the moon and back alomst 1500 times. The sun is 93,000,000 miles away, so your DNA would reach there and back about 4 times!

Interestingly, no more than 1.5 percent of the human genome contains DNA that help…

Really. Or to use a more “explosive” illustration, multiply the world’s entire nuclear stockpile seven million times and detonate it. That’s also about one second’s solar output. Or put another way … well, you get the point; the Sun puts out a lot of energy.

We only avoid being incinerated by this 800,000 mile wide, 100,000,000 degree inferno because, like a light bulb, the Sun radiates in every direction. That, and the fact that we are 93,000,000 miles away, allows us to experience sunshine as a gentle blessing rather than an incinerating white-hot blast.

But where does so much energy come from? That question stumped scientists from the late 1800’s until the early 1900’s. By then science had come to realize that the earth was billions of years old, not just thousands as previously believed. But they couldn’t figure out what could have powered the Sun that energetically for so long.

The general answer came with the new science of nuclear physics and with Einstein’s postulation of his fam…

Really. The top of towers of the Verrazano - Narrows Bridge at the mouth of the Hudson river in New York City are tilted almost two inches further apart than the base thanks to the curve of the Earth's surface.

Actually, there are a lot of amazing things about that not-so-famous bridge.

When it opened in 1964, at 4260 feet it was the longest suspension bridge in the world, exceeding the Golden gate completed in 1937, by 60 feet. Today it's the longest single span in North America and the seventh longest in the world. (The longest is the 6,529 foot Akashi-Kaikyo Bridge in Japan, completed in 1998.)

The Verrazano - Narrows Bridge contains enough concrete to construct a single lane highway from New York to Washington, and if the wires that make up the suspension cables were laid end-to-end they would reach 143,000 miles, more than halfway to the moon.

On hot days, the double-decker road bed expands almost six feet and sags 12 feet lower, something that ships passing underneath have …